linux-sg2042/arch/mips/bcm63xx/irq.c

254 lines
5.5 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
* Copyright (C) 2008 Nicolas Schichan <nschichan@freebox.fr>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <asm/irq_cpu.h>
#include <asm/mipsregs.h>
#include <bcm63xx_cpu.h>
#include <bcm63xx_regs.h>
#include <bcm63xx_io.h>
#include <bcm63xx_irq.h>
/*
* dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
* prioritize any interrupt relatively to another. the static counter
* will resume the loop where it ended the last time we left this
* function.
*/
static void bcm63xx_irq_dispatch_internal(void)
{
u32 pending;
static int i;
pending = bcm_perf_readl(PERF_IRQMASK_REG) &
bcm_perf_readl(PERF_IRQSTAT_REG);
if (!pending)
return ;
while (1) {
int to_call = i;
i = (i + 1) & 0x1f;
if (pending & (1 << to_call)) {
do_IRQ(to_call + IRQ_INTERNAL_BASE);
break;
}
}
}
asmlinkage void plat_irq_dispatch(void)
{
u32 cause;
do {
cause = read_c0_cause() & read_c0_status() & ST0_IM;
if (!cause)
break;
if (cause & CAUSEF_IP7)
do_IRQ(7);
if (cause & CAUSEF_IP2)
bcm63xx_irq_dispatch_internal();
if (cause & CAUSEF_IP3)
do_IRQ(IRQ_EXT_0);
if (cause & CAUSEF_IP4)
do_IRQ(IRQ_EXT_1);
if (cause & CAUSEF_IP5)
do_IRQ(IRQ_EXT_2);
if (cause & CAUSEF_IP6)
do_IRQ(IRQ_EXT_3);
} while (1);
}
/*
* internal IRQs operations: only mask/unmask on PERF irq mask
* register.
*/
static inline void bcm63xx_internal_irq_mask(unsigned int irq)
{
u32 mask;
irq -= IRQ_INTERNAL_BASE;
mask = bcm_perf_readl(PERF_IRQMASK_REG);
mask &= ~(1 << irq);
bcm_perf_writel(mask, PERF_IRQMASK_REG);
}
static void bcm63xx_internal_irq_unmask(unsigned int irq)
{
u32 mask;
irq -= IRQ_INTERNAL_BASE;
mask = bcm_perf_readl(PERF_IRQMASK_REG);
mask |= (1 << irq);
bcm_perf_writel(mask, PERF_IRQMASK_REG);
}
static unsigned int bcm63xx_internal_irq_startup(unsigned int irq)
{
bcm63xx_internal_irq_unmask(irq);
return 0;
}
/*
* external IRQs operations: mask/unmask and clear on PERF external
* irq control register.
*/
static void bcm63xx_external_irq_mask(unsigned int irq)
{
u32 reg;
irq -= IRQ_EXT_BASE;
reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
reg &= ~EXTIRQ_CFG_MASK(irq);
bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}
static void bcm63xx_external_irq_unmask(unsigned int irq)
{
u32 reg;
irq -= IRQ_EXT_BASE;
reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
reg |= EXTIRQ_CFG_MASK(irq);
bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}
static void bcm63xx_external_irq_clear(unsigned int irq)
{
u32 reg;
irq -= IRQ_EXT_BASE;
reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
reg |= EXTIRQ_CFG_CLEAR(irq);
bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
}
static unsigned int bcm63xx_external_irq_startup(unsigned int irq)
{
set_c0_status(0x100 << (irq - IRQ_MIPS_BASE));
irq_enable_hazard();
bcm63xx_external_irq_unmask(irq);
return 0;
}
static void bcm63xx_external_irq_shutdown(unsigned int irq)
{
bcm63xx_external_irq_mask(irq);
clear_c0_status(0x100 << (irq - IRQ_MIPS_BASE));
irq_disable_hazard();
}
static int bcm63xx_external_irq_set_type(unsigned int irq,
unsigned int flow_type)
{
u32 reg;
struct irq_desc *desc = irq_desc + irq;
irq -= IRQ_EXT_BASE;
flow_type &= IRQ_TYPE_SENSE_MASK;
if (flow_type == IRQ_TYPE_NONE)
flow_type = IRQ_TYPE_LEVEL_LOW;
reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
switch (flow_type) {
case IRQ_TYPE_EDGE_BOTH:
reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
reg |= EXTIRQ_CFG_BOTHEDGE(irq);
break;
case IRQ_TYPE_EDGE_RISING:
reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
reg |= EXTIRQ_CFG_SENSE(irq);
reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
break;
case IRQ_TYPE_EDGE_FALLING:
reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
reg &= ~EXTIRQ_CFG_SENSE(irq);
reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
break;
case IRQ_TYPE_LEVEL_HIGH:
reg |= EXTIRQ_CFG_LEVELSENSE(irq);
reg |= EXTIRQ_CFG_SENSE(irq);
break;
case IRQ_TYPE_LEVEL_LOW:
reg |= EXTIRQ_CFG_LEVELSENSE(irq);
reg &= ~EXTIRQ_CFG_SENSE(irq);
break;
default:
printk(KERN_ERR "bogus flow type combination given !\n");
return -EINVAL;
}
bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) {
desc->status |= IRQ_LEVEL;
desc->handle_irq = handle_level_irq;
} else {
desc->handle_irq = handle_edge_irq;
}
return 0;
}
static struct irq_chip bcm63xx_internal_irq_chip = {
.name = "bcm63xx_ipic",
.startup = bcm63xx_internal_irq_startup,
.shutdown = bcm63xx_internal_irq_mask,
.mask = bcm63xx_internal_irq_mask,
.mask_ack = bcm63xx_internal_irq_mask,
.unmask = bcm63xx_internal_irq_unmask,
};
static struct irq_chip bcm63xx_external_irq_chip = {
.name = "bcm63xx_epic",
.startup = bcm63xx_external_irq_startup,
.shutdown = bcm63xx_external_irq_shutdown,
.ack = bcm63xx_external_irq_clear,
.mask = bcm63xx_external_irq_mask,
.unmask = bcm63xx_external_irq_unmask,
.set_type = bcm63xx_external_irq_set_type,
};
static struct irqaction cpu_ip2_cascade_action = {
.handler = no_action,
.name = "cascade_ip2",
};
void __init arch_init_irq(void)
{
int i;
mips_cpu_irq_init();
for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
set_irq_chip_and_handler(i, &bcm63xx_internal_irq_chip,
handle_level_irq);
for (i = IRQ_EXT_BASE; i < IRQ_EXT_BASE + 4; ++i)
set_irq_chip_and_handler(i, &bcm63xx_external_irq_chip,
handle_edge_irq);
setup_irq(IRQ_MIPS_BASE + 2, &cpu_ip2_cascade_action);
}